title: Comorbidities are associated with poorer outcomes in community patients with rheumatoid arthritis.
abstract: OBJECTIVE
  To evaluate the impact of comorbidities on achieving remission by examining changes in the clinical disease activity index (CDAI) in RA patients in the community-based Consortium of Rheumatology Researchers of North America (CORRONA) registry.
  
  
  METHODS
  A subcohort of 1548 RA subjects with varying disease duration met the following inclusion criteria: started a DMARD/biologic agent, continued therapy ≥ 3 months, CDAI ≥ 2.8 at study entry and followed longitudinally from baseline to follow-up (mean time 7.46 months). Patients reported comorbidities according to a standardized list of 33 conditions. Entry characteristics were compared across age categories using one-way analysis of variance. Linear and logistic regression models were constructed to assess characteristics [e.g. age, disease duration, number of previous DMARDs/biologics, baseline modified health assessment questionnaire (MHAQ), baseline CDAI and number of comorbidities] associated with primary outcomes: change in CDAI (baseline to follow-up) and CDAI remission (yes/no).
  
  
  RESULTS
  Although disease activity measures at entry were similar across age categories, older patients had more comorbidities, less improvement in CDAI/MHAQ and were less likely to attain remission at follow-up. However, after adjusting covariates an increasing number of patient-reported comorbidities and higher baseline CDAI (but not age) were consistently and independently associated with a lower likelihood of clinical improvement or remission (P < 0.001).
  
  
  CONCLUSIONS
  In this observational cohort of community RA patients an increasing number of patients reported comorbidities, independently correlated with less CDAI improvement over time. These results reaffirm that comorbidities may be an important factor in consideration of treat-to-target recommendations and aid in understanding achievable RA therapeutic goals.
authors.affiliation: University of California at Los Angeles, 1000 Veteran Avenue, Rehab Building 32-59, Los Angeles, CA 90095, USA. vranganath@mednet.ucla.edu.
authors.forename: Veena K
authors.initials: VK
authors.lastname: Ranganath
authors.forename: Paul
authors.initials: P
authors.lastname: Maranian
authors.forename: David A
authors.initials: DA
authors.lastname: Elashoff
authors.forename: Thasia
authors.initials: T
authors.lastname: Woodworth
authors.forename: Dinesh
authors.initials: D
authors.lastname: Khanna
authors.forename: Theodore
authors.initials: T
authors.lastname: Hahn
authors.forename: Catherine
authors.initials: C
authors.lastname: Sarkisian
authors.forename: Joel M
authors.initials: JM
authors.lastname: Kremer
authors.forename: Daniel E
authors.initials: DE
authors.lastname: Furst
authors.forename: Harold E
authors.initials: HE
authors.lastname: Paulus
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D018501:Antirheumatic Agents / Q000627:therapeutic use*; D001172:Arthritis, Rheumatoid / Q000188:drug therapy* / Q000453:epidemiology*; D001688:Biological Products / Q000627:therapeutic use; D015897:Comorbidity; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D012074:Remission Induction; D012720:Severity of Illness Index; D016896:Treatment Outcome; D014481:United States / Q000453:epidemiology; D055815:Young Adult
chemical_list: D018501:Antirheumatic Agents; D001688:Biological Products
keywords: age; comorbidities; remission; rheumatoid arthritis